Geoscience Reference
In-Depth Information
(5.4)
h
f
f
)
D
⋅
1
2
Dh
(5.5)
bh
(
h
)
h
+
π
⋅
⋅
where:
h
=
filled height of the geotextile tube [m];
f
=
degree of filling with respect to the cross-sectional area (percentage of the
area of the theoretical circle) [
−
];
D
=
diameter of the geotextile tube at 100% filling [m];
b
=
filled width of the geotextile tube [m].
Table 5.3 shows the dimensions (and thus the resultant shape) of a geotextile
tube for filling levels between 60% and 100% as a function of the radius (
R
) of
the circular diameter of a 100% filled geotextile tube, using the formulae given in
Appendix D. The shaded part of the table indicates the most common degree of fill-
ing values. Note that these are indicative values and are dependent on the size of the
geotextile tube.
Sometimes the term “degree of filling” may be confusing. In this publication
(and in the literature), the degree of filling is expressed as a percentage of the theo-
retical cross-sectional area of a 100% filled geotextile tube. In practice, however, the
degree of filling is usually related to the theoretical height of the tube at 100% fill-
ing. This is because it is almost impossible to measure the cross-sectional area while
filling. As these two values are different, it is therefore advisable to clearly indicate
on which parameter the fill rate is based. This is even more important for geotextile
containers (to be discussed in Chapter 6), where the degree of filling is sometimes the
volume of the geotextile container divided by the volume of the barge that is used for
dumping.
Table 5.3
Dimensions and shape of geotextile tube for various levels of filling
(tube above water).
f [-]
r [m]
b [m]
h [m]
1.00
1.00 R
2.00 R
2.00 R
0.95
0.70 R
2.28 R
1.59 R
0.90
0.58 R
2.40 R
1.42 R
0.85
0.50 R
2.49 R
1.29 R
0.80
0.43 R
2.56 R
1.17 R
0.75
0.37 R
2.63 R
1.07 R
0.70
0.32 R
2.69 R
0.98 R
0.65
0.28 R
2.74 R
0.89 R
0.60
0.24 R
2.79 R
0.81 R
f
=
degree of filling.
r
=
radius of the quadrants on both sides of the straight base of the geotextile tube.
b
=
maximum width of the geotextile tube.
h
=
height of the geotextile tube.
R
=
radius of the theoretical circle for 100% filling (
R
=
D/2
).
